Magnetic record editing device



Sept. 23, 1952 o. B. GUNBY MAGNETIC RECORD EDITING DEVICE Filed May 51, 1950 m/ I. ay; i v

Patented Sept. 23, 1952 Olin B. Gunby, -Los -Angeles, -Calif., assignor .to Radio Corporation .of Americana corporation (of Delaware elim nation May 3 95Q, .S e 1N9- ,6 35% 1=2Claims. (c1. 17-9-1002) This invention relates to sound reproducing apparatus, and particularly to am aieti s arla record reproducing and editing device: With the advent of magnetic sound recording and reproduction, editing "devices are needed tb cut and edit the soundtrack. This as "true particularly in motion picture production ivher the sound record is recorded on-a fllrn-separatedrorn the film on which the "concomitan pi re ar photographed. In prior motion picture sound recording systems, a photographic'ftrackuvas visible after development. Thus a particular point on thetrack could belo'cated' isuany; 'To locate such a point at 'whichfthe -tr ack is-to'be cut or is to be fifiliffiedv injsomle manner-or other,

a device such as di sclosed and clalmedfin UkS. Patent No. 2,235;029 of Marchl'8, l941, is used. Since magnetic sound records are invisible, other types of devices arerequired toflocate the desired point on a magneticsound'trackf-In 'copending application," SeruNb, 9300filed February 18, 1948, a magnetic ;soundtra' ck f editing system is disclosed and claimedthis systemsuper'imposing the image of thesoundtrack uponthe'nia netic track.

My system is 'one wherein, through agsimple adjustment of the slip-rings connected to-arotating magnetic head, the-exact point at{which the film is to be modified flis indicated. fllhe use of rotating magnetic 'headsfto reproduce a stationary magnetic record e I heads being shown; in the above mentioned copending application andin U. S.-"P atent=-No. 2,352,023 of July 20, 1944, and in U.- S.--'Patent No. 2,424 295 ofjJuly-; '22, 1947. Hovvever, the

simple reproduction of; the'lihnby rotating heads is not of itself sufilclently accurate to proyide the exact point at which the soundtrack is to be changed or the filmcut. My device permits the exactlocating of any particularspot on the 'film quickly and accurately.

The principal Object of -the'invention,therefore, is to facilitate theeditin e n -1 f particular point on an invisible soundtrack.

Another object of the invention is to provide an improved magnetic sound :record 1 editing device.

A further objector :the invention; is :to provide an improved magnetic .soundqeditor which will accurately locate a particular pointona magnetic sound track.

Although the novel {featuresyvhicharebelieved to be characteristic of ibis/invention ivill be pointed out with lparticula'rityl in the, appended claims, the manner .of its organisation and the mode of its operation willbe"betterunderstood i'epr'odu'cing amplifier-i1 andithenztofthellondspea er 2 3 over I conductors 2 8; isf'r'nountedfor partial: rotation on alshaftr32jnin a'rie1 r2 and on shaft 39" coaxial therewith. {I'he 30 shaft 30 is supported bya bracket 29 attached .2 byreferring to thefollowing description, read in conjunction with the "accompanying drawing, forming 'a part'h'ereof, in'which the single figure is a perspective diagrammatic view of a system embodying the invention.

' "Referring now to the drawing-amagnetic film 5 [is shown'passing from a r'eeltunder a guide roller 1 overa stationary shoe-8 under a 'gui'de 'rollerffi' and to'reel In. "These elementsiare mounted-on a panel l2 behind whichiis mounte'd ametsr 13 having a drive pinion l 4 on=the motor "shaft. Mounted for rotation' bythe pinionz'lAis a geared casting [6, on which a magnetic ;hea'd H is mounted, and which-isconnected by' conductors 18 to a pair of slip rihgst'lS and 120. "It

will The "noted that the-shoe :8 I is narrower -than the film '-5, "so that the filin 1 overhangs: the ='h0e and permits tiiegapil of: the headfl' t'otcontact that portion of the -film 'unsupportedlwby'rthe shoe s. "'To carrythe output of the head .'l1tto a,-'1oud speaker 23', two conducting .tbrush'es 52:4 and :25

are i in contact with thesslip rings I 9 and land are mounted on an insulated bracketi:25. Ihe brushes are connected' overicondu'ctors 26 to a The, bracket to the panel, and may be turnedby a hand wheel 3|. Rotation of the shaft 30 moves theibrushes fZ'R and 2 5 over "the slip rings -19 andrifl. .IIhe upper end of the 'back portionof the bracket cqnt ms' an indicator plate 33, on which; isfan panel has a-wmg lock-nut thereon to..-1.'lock "thebracket 2 5 "in position. 'Thus, if the i bracket fisrotated, the plate 33 will move likewise,-,:and

the: anow 'siwm correspond with the positionof 'the brushes za nd z t'. Y

Toope'rate the-editor, the head I 1 is r held stationary 'in' any position vvh'ere'itcontactslthefiim The direction offthe film ov r the ha'd' tvilrdewill be reproduced; and whenlthepoint soughtqis 1 heard; thenlm is stopped and backed up to approximately that-point. The motor l 3;is then energized --and' the 1 head i rotated at a speed -'approximating.,the speed :;of.,;the ;f l m during "recording. If .thehointtobeafoundis not on the shoe 8, the filmvzmay Joe either II 1 Q/f6d ,l forward or backward by the handles 36 and 31 until the point is being reproduced. The film is then held stationary and the brushes 24 and 25 are rotated until the point sought is found. For instance, if the point to be located is the beginning of a sound passage, then the brushes are moved to the point where the sound begins to be reproduced while on the shoe 8, and the arrow will point to this spot on the film.

To accomplish this result, slip ring I9 is only conducting over a portion of its length substantially corresponding to the length of the shoe 8, while the other portion of the ring is non-conducting. That is, portion 4!! may be conducting and portion 4! may be non-conducting. The other ring is conducting over its entire length. Thus, if the entire portion of the film on the shoe 4 conducting segment and a non-conducting segment.

4. A magnetic sound track editor in accordance with claim 2, in which means are provided for adjusting said brushes and for locking said brushes in position with respect to a point on said film.

5. An editor for locating a certain point on a magnetic record, comprisinga stationary shoe for supporting a magnetic film, a longitudinal portion of said film overhanging said shoe, a

rotatable magnetic head adapted to contact said overhanging portion of said film, a pair of slip rings, a pair of simultaneously movable brushes 8 had a signal thereon, no portion would be reproduced unless brush 24 was contacting con-.

ducting segment 40. If the non-conducting segment 4| were in contact with the brush while the head IT was in contact with the film, there would be no reproduced signal, regardless of whether or not a signal was on the film. If the brush 24 was in contact with the conducting segment 40 of the ring 19 while the head was not contacting the film, there would also be no reproduced signal. Thus, the only time that a signal will be reproduced in the loudspeaker 23 is when the conducting portion 40 of the slip ring I9 is in contact with the brush 24 during the period that the head [9 is in contact with a signal portion of the film.

Now, should the beginning of a sound portion lie on the shoe 8, the brushes 24 and 25 may be rotated until the signal point on the film corresponds to the brush position point which will be when the head I! contacts the sound portion. At this time, the arrow will point exactly to that point and the sound track may be marked and the film modified or cut at this point either then or at a later time. In the event the general location of the point has been selected by a footage number, the film drives a sprocket 44 connected to a footage counter 45. Thus, when the,

film reaches a certain point, as indicated by the footage indicia, it can be stopped and the motor l3 energized. Although a drive pinion and gear are illustrated, the pinion M may be a smoothly rimmed puck in contact with a rim of the casting [6.

I claim:

1. A magnetic sound track editor comprising means for supporting a portion of a magnetic film in an arc, a magnetic head, means for rotating said magnetic head whereby said head makes contact with the unsupported portion of said magnetic sound film, a sound reproducer, and means for conducting the output of said head to said reproducer, said means including a pair of rotatable brushes and a pair of slip rings,

one of said rings having a portion thereof conducting and another portion thereof non-conducting.

2. A magnetic sound track editor comprising a stationary magnetic sound track film, a magnetic reproducing head, means for rotating said head in contact with a portion of said film, a pair of slip rings, brushes adjustable over said rings, a sound reproducer, means for connecting said reproducer to said head through said rings and brushes, and means for indicating the position of said brushes with respect to said film.

3. A magnetic sound track editor in acordance with claim 2, in which one of said rings has a incontact with said rings, and a reproducing system connected to said head through said rings and brushes, one of said rings connecting and disconnecting said head to and from said reproducing system periodically.

6. An editor in accordance with claim 5, in which said one ring has two sections, one of which is conducting, and the other of which is non-conducting.

7. An editor for locating a certain point on a magnetic record, "comprising a stationary shoe for supporting a magnetic film, a longitudinal portion of said film overhanging said shoe, a rotatable magnetic head adapted to contact said overhanging portion of said film, a pair of slip rings, a pair of brushes in contact with said rings, a reproducing system connected to said head through said rings and brushes, one of said rings connecting and disconnecting said head to and from said reproducing system periodically, a partially rotatable bracket for said brushes, and means for adjusting said brushes over an arc corresponding to the arc of said shoe.

8. An editor for locating a certain point on a magnetic record, comprising a stationary shoe for supporting a magnetic film, a longitudinal portion of said film overhanging said shoe, a rotatable magnetichead adapted to contact said overhanging portion of said film, a pair of slip rings, a pair of brushes in contact with said rings, a reproducing system connected to said head through said rings and brushes, one of said rings connecting and disconnecting said head to and from said reproducing system periodically, said one ring being divided into conducting and nonconducting portions and a bracket for said brushes, said bracket supporting said brushes and being rotatable to adjust said brushes over said rings through an arc corresponding to the arc of said shoe.

9. An editor for locating a certain point on a magnetic record, comprising a stationary shoe for supporting a magnetic film, a longitudinal portion of said film overhanging said shoe, a rotatable magnetic head adapted to contact said overhanging portion of said film, a pair of slip rings, a pair of brushes in contact with said rings, a reproducing system connected to said head through said rings and brushes, one of said rings connecting and disconnecting said head to and from said reproducing system periodically, and a footage counter, said footage counter being actuated by said film to determine the general position of a point on said film to be located.

10. A magnetic sound track editor comprising means for holding a portion of a sound track film stationary, a magnetic reproducing head, means for intermittently moving said head in contact with a portion of said film, means for translating the signals on said film detected by said reproducing head into, corresponding audible sound waves, slidable contact means electrically connecting said head with said translating means, and means for adjusting certain elements of said slidable contact means with respect to one another to vary the portion of said stationary film being reproduced to determine and. locate a particular point on said film.

11. A magnetic sound track editing device comprising a movable magnetic pickup head, means for supporting a portion of a film so as to be physically contacted over a portion thereof by said head, means for intermittently moving said head into physical contact with said film portion, electrical contact means connected to said head, means for translating the currents picked up by said head into audible sound waves, electrical contact means connected to said translating means, means for adjusting one of said contact means with respect to said other contact means to vary the section of said film portion being translated into audible sound waves to determine and locate a particular point on said film portion, and means for indicating said point.

12. A magnetic sound track editor comprising means for holding a portion of a magnetic sound track film stationary, a magnetic reproducing head, means for cyclically moving said head in contact with and over a portion of said film, means for translating the signals on said film detected by said reproducing head into corresponding audible sound waves, and means for periodically electrically connecting said head with said translating means as said head moves over said film, said means including means for rendering said connecting means effective to connect said head to said translating means over varying sections of said film portion to determine and locate a particular point on said film.

OLIN B. GUNBY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,825,439 Cawley Sept. 29, 1931 2,348,050 Barnstyn May 2, 1944 

